Building automation systems are well known and widely used in residences and industrial environments. Typically, multiple systems and devices such as climate control, lighting, temperature control and the like are controlled by a controller located remotely from the systems to be controlled.
Power Line Carrier (PLC) technology or protocol is one technology that has existed for over twenty years and uses a command signal transmitted over the existing 120 volt home electrical wiring system. However, some PLC systems are subject to interference from other electrical systems, creating such inconveniences as unanswered or false commands.
Wireless technology using radio frequencies (RF) are sometimes used in newer home constructions, but more typically is used in older homes for expanding existing hardwired systems. Typically, a command signal is transmitted by radio waves to a central controller. However, this topology requires additional hardware and space to accommodate the central controller and is usually a closed platform, which prevents the user from modifying certain logic sequences or adding specific hardware functionality.
Low voltage hardwired systems have been used for over forty years to create a communications network within the home. This technology uses communications over a data path over wires placed in the walls of the house before they are covered with plaster. Each control device includes a copper wire connecting it to a main controller. Furthermore, with the advent of computer controlled systems and controlling software, the remote control of the multiple systems and devices would appear to be straightforward. However, to install such systems in buildings, typically the interior of the buildings have to be re-modeled. In residential environment, such as homes, remodeling can be prohibitively expensive and typically requires structural modifications to walls and existing wiring to install additional complex wiring to accommodate such controller systems.
A number of examples have been disclosed which address the aforesaid problems. In U.S. Pat. No. 6,980,080, issued on Dec. 27, 2005 to Christensen et al., a wireless home automation system is disclosed in which multiple controllers control a variety of functions using a two-way communication with a number of devices such as lighting, burglar alarms, thermostats and the like. This system appears to rely on learnt information between the controllers, which is stored in a memory for each controller. In U.S. Pat. No. 6,967,565 issued on Nov. 22, 2005 to Lingemann, a building automation system is disclosed which uses multiple user interface units with touch screens, power drivers and a controller. All of these are connected to a common trunk conductor. From the user interface unit, multiple electrical devices in a building may be controlled by the units and wireless remote controls. In U.S. Pat. No. 6,865,596, issued on Mar. 8, 2005 to Barber et al., a master controller in a control area network system is disclosed, within a larger control area network, and which may have a number of devices connected to it. The master controller has a device manager which provides a so-called “virtual device”. U.S. Pat. No. 6,813,525, issued on Nov. 2, 2004 to Reid et at discloses a programmable control system which includes a control module having one or more inputs to which a sensor device can be connected. Also included is an external actuator device which can be used for manual override and status feedback. This system appears to rely on a learning mode and a memory to store characteristics of the external sensor. In U.S. Pat. No. 6,192,282, issued on Feb. 20, 2001 to Smith et al., a building automation system, which is modular in design is disclosed and which minimizes the amount of instruction needed to control a building system. The system appears to operate by translating control instructions in one control protocol to control instructions in a second control protocol. In U.S. Pat. No. 5,706,191, issued on Jan. 6, 1998 to Bassett et al., a method for bringing an appliance and/or a mechanical/electrical system of a residence into communication with another is disclosed. To achieve this, each appliance is provided with an appliance interface module apparatus. U.S. Pat. No. 5,557,545, issued on Sep. 17, 1996 to Loffel et al., discloses an automatic control for a power plant with a number of interacting plant components having an automation system which is shared by the plant components, and with automation devices executing various functions. The automation devices are connected to each other and to a master control unit though a data bus which transmits plant relevant data. U.S. Pat. No. 5,289,365, issued on Feb. 23, 1994 to Caldwell et al., discloses a module electrical control system for controlling office equipment. The system includes a number of control modules which are interconnected with an input module via a bus assembly. A keypad appears to generate an input signal, an output port to which the system bus assembly is connected and a circuit which is responsive to the input signal for supplying a command signal to the output port. The system bus assembly includes at least two signal channels, one of which is selectively supplied with a switched low voltage signal, the other being selectively supplied with a data signal. In U.S. Pat. No. 5,128,855, issued on Jul. 7, 1992 to Hilber et al., a system for controlling an operating installation of a building's automation system is disclosed. The system comprises a control module which serves as a master transmitter-receiver and a function module, which serves as a slave transmitter. A bus connection includes a bus rail which connects the control module and the function module to transmit addresses and data, and operating voltages. In US patent application Ser. No. 2005/0125083, published on Jun. 9, 2005 to Kilco, a server-based system for providing a substantially automated operation and control of a number of functions within a premises, such as residence, is disclosed.
The aforesaid designs suffer from a number of significant drawbacks. None of the designs appear to be retrofittable into an existing household wiring network using existing household electrical boxes. The designs appear to be complex and may be prohibitively expensive to install into industrial, commercial or household environments. Some of the designs appear to be server based, which may not be practical for household systems control. In one example, each appliance to be controlled appears to be provided with an interface module, which presumably would mean that each household appliance would have to be wired up to its AIM. This may be prohibitively expensive and would require modifying existing appliances.
Thus, there is a need for an improved controller for remotely controlling multiple electronic hardware devices, which is simple to install and modular with straightforward expandability.